Inside door handle 55 ford

[Dorf55]

I have replaced my inside door handles on my 55 fairlane. The old handles had a round back on them and the new handles have a triangle shape to them. The old handles fit tight no problem, the new handles have a hard time staying on, it's as if the clips don't fit tight around the new handles with the triangle shaped back.
If I shut the door hard enough the new handles will fall of, I put the old handles back on and no problem.
I purchased the clips with the new handles:
Can I buy new handles with the round back ?
Maybe I have the wrong clips for the new handles?